Field of the Invention
The present invention relates to menthol-sorbed activated charcoal, a cigarette filter, and a filter-tipped cigarette.
Description of the Related Art
In cigarettes, flavorants such as menthol are used to improve the intrinsic aroma and taste of the cigarettes. As menthol flavoring method, the addition to cut tobacco, the addition to inner packing paper of a package, and the addition to a filter are known. Encapsulation of menthol is also a common practice.
It is known that, in the addition of menthol to cut tobacco or inner packing paper, if the amount of menthol is increased, more brown stains occur on the cigarette paper of the tobacco rod during storage of the cigarette. The stains are attributable to the release of dyestuffs from cut tobacco upon the volatilization of menthol.
On the other hand, the use of menthol capsules allows the control of the occurrence of stains on cigarette paper and the deterioration of menthol in smoke. However, the use of menthol capsules requires the processes of the production of the capsules and incorporation of the capsules into the cigarette. As a result, the production cost of cigarette will increase.
On the other hand, U.S. Pat. No. 3,236,244 describes a filter element containing activated charcoal. Menthol is adsorbed to the activated charcoal, to add to a tobacco flavor.